I've added the facebook share button (https://developers.facebook.com/docs/share/) to my website and I'm trying to determine whether or not someone shares a link. Any ideas on whether this can be done and how? I'm open to using the like button instead of the share button.

one thing that i haven't mentioned explicitly in that answer, but it's there in the code, is that you have to subscribe to the edge.create event. When you see the respective code, you'll understand, ask for clarifications if required.
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bool.devDec 28 '11 at 19:39